International Research Journal of Environment Sciences________________________________ ISSN 2319–1414Vol. 3(6), 75-80, June (2014) Int. Res. J. Environment Sci. International Science Congress Association 75 Evaluation of physicochemical and bacteriological quality of Oued Merzeg (Suburbain of Casablanca, Morocco) Jihad Mounjid1,2*, Nozha Cohen, Souad Fadlaoui et Said Oubraim1 Laboratory of Ecology and Environment, Faculty of Sciences Ben Sik, University Hassan II-Mohammedia, Casablanca, MOROCCO Laboratory of Microbiology and Hygiene of Food and Environment, Institute Pasteur of Morocco, Casablanca, MOROCCO Available online at: www.isca.in, www.isca.me Received 27th May 2014, revised 15th June 2014, accepted 22nd June 2014 AbstractThe aim of this study was to determine the physicochemical and microbiological quality of Oued Merzeg. The analyzed waters present an organic pollution represented by the concentration of the organic (DBO5, DCO, Pt, PO4 and NH4). However, analysis of physical parameters and indicators of mineralization, conductivity, salinity, chlorides, sulfates, and water sampled showed a significant mineralization. Parameters monitoring fecal contamination, total coliforms (TC), fecal coliforms (FC) and fecal streptococci (FS), reveal a significant fecal contamination. Water quality of Oued Merzeg pleads for non-conformity of water to be used directly in all areas because they exceed the normative limits generally accepted. The principal component analysis (PCA) evaluated and interpreted complex water quality data sets and apportioned of pollution sources to get better information about water quality of Oued Merzeg. Keywords: Oued Merzeg, physicochemical, bacteriological, PCA. IntroductionThe quality of the river basins is degraded due to the indiscriminate disposal of anthropogenic wastes and leaching of pollutants due to development of an area, which sees an increase of population, urbanization and industrialization. Thus, it is important to carry out river quality monitoring in order to detect the changes of the water quality and to identify the pollution sources. There are various water quality parameters to be measured and considered in order to determine the health of the river water and to develop a water quality index. These parameters can be categorized as physicochemical and biological. In Morocco, the situation of the river becomes increasingly worrying because of the large amounts of untreated discharges pollutants which are discharged into the aquatic ecosystems. To study the situation closely, we chose a peri-urban watercourse which knows a growing demography and a continuous development of industry along Oued Merzeg shores and its tributary Oued Sierni. Oued Merzeg receives treated waters from the WWTP Berrechid treating a flow of about 1850 m3 /j, while its tributary Sierni receives industrial discharges Had Soualem. This workis aimed to assess the degree of pollution of the Oued Merzeg through a characterization of physicochemical and bacteriological water of six stations from upstream to downstream. To highlight the overall quality of these waters and its spatio-temporal evolution in the studied streams, we found interesting to make a synthesis of these results by the statistical method (components main ACP analysis), to identify the relationship between the different variables and also to study the spatial distribution of the study sites. Material and Methods Study area: Oued Merzeg is located 20km south-east of Casablanca, on the coastal Chaouia. It is bounded on the north by the Atlantic Ocean, to the south and west by the province of Settat and east by the province of Médiouna. The river is part of the watershed of Oued Coastal Atlantic, covering an area of 157.8 km2 6. The climate of the coastal Chaouia is semi-arid with an oceanic influence. The average annual rainfall is 400 mm, while the average temperature is 25°C. The river is located near industrial areas, notably Had Soualem whose discharges are drained by its tributary oued Sierni (SO) and a few scattered throughout the units of Khyayta region.Sampling and analysis methods: Six stations were selected along the stream according to the nature of wastewater (sewage, natural waters), ease of access and collection and also the situation of sampling over pollutant release points (figure-1). 14 samples were completed during a period from February 2011 to March 2012. The State of Oued Merzeg is apprehended from measurements of 16 variables physicochemical and bacteriological. The methods used to determine these variables are those advocated by AFNOR. The measures in situ of pH, electrical conductivity (CE), dissolved oxygen (do) and turbidity (Turb) have respectively been carried out thanks to a pH meter WTW, conductivity WTW, WTW Oximeter and a turbid meter EUTCH TN-100. International Research Journal of Environment Vol. 3(6), 75-80, June (2014) International Science Congress Association Study area a Chemical analyses are: chlorid es (Cl), sulfates (SO (NO-), nitrite (NO), ammonium (NH ), ortho total phosphorus (PT), BOD5 and COD. The enumeration of indicator bacteria of fecal contamination have dealt totals (CT) coliforms and fecal coliforms (FC), as well as fecal streptococci (SF).Results and Discussion Physicochemical characterization: PH, Conductivity, Salinity: The spatial variation of pH at Oued Merzeg shows little fluctuation (± 0.52) with alkaline waters where a minimum is observed i n SO (8.14) and a maximum in M4 (8.66). The maximum values of the EC and salinity are recorded of downstream in M5 (3.47 mS/cm and 1.28 g /l, respectively) (Fig.2a), which is influenced by the proximity of the marine environment. COD and BOD5: At Oued Merzeg, there is a gradient of cod and BOD5 from upstream to downstream, which testifies the self- purifying effect of the river. The contents of COD and BOD5 of treated wastewater of the WWTP Berrechid respectively from 80.79 and 50.46 mg O2/l M1 to 29.57 8.27 mgO2/l M5 (figure 2b) or an abatement rate of approximately 83.61% for BOD5 and 63.40 % for COD. Nevertheless, an organic enrichment is observed at the level SO due to the discharge of Had Soualem and M3 which is close to a farm where the animals have free access to the waterways. Turbidity: The spatial variation of turbidity varies from one station to another. The maximum levels are recorded in SO (134.11 NTU), as industrial discharges. In Had Soualem, turbidity is marked by a very dark color fr om textile industries; Environment Sciences_______________ _________________________ International Science Congress Association Figure-1 Study area a nd water quality sampling sites es (Cl), sulfates (SO ), nitrate ), ortho -phosphate (PO), total phosphorus (PT), BOD5 and COD. The enumeration of indicator bacteria of fecal contamination have dealt totals (CT) (FC), as well as fecal streptococci PH, Conductivity, The spatial variation of pH at Oued Merzeg shows little fluctuation (± 0.52) with alkaline waters where a minimum n SO (8.14) and a maximum in M4 (8.66). The of the EC and salinity are recorded of downstream in M5 (3.47 mS/cm and 1.28 g /l, respectively) (Fig.2a), which is influenced by the proximity of the marine there is a gradient of cod and BOD5 from upstream to downstream, which testifies the The contents of COD and BOD5 of treated wastewater of the WWTP Berrechid O2/l M1 to 29.57 and 2b) or an abatement rate of approximately 83.61% for BOD5 and 63.40 % for COD. Nevertheless, an organic enrichment is observed at the level SO due to the discharge of Had Soualem and M3 which is close to a have free access to the waterways. The spatial variation of turbidity varies from one station to another. The maximum levels are recorded in SO (134.11 NTU), as industrial discharges. In Had Soualem, om textile industries; whereas at M3 (88.69 NTU) (fig ure the surrounding agricultural land. Total phosphorus and orthophosphate pollution is observed upstream of the river where the values total phosphorus and orthophosphate are of the order of 6.02, 3.53 mg/l in M1 and 5.46, 2.37 mg /l in M2 ( decreasing gradient was observed with a reduction in downstream respectively of the order of 57.47% and 53.82%. In addition, the pollution load drained by t discharges from Had Soualem has low levels of phosphorus compounds (2.65 mg /l PT and 1.38 mg /l PO Chlorides and sulphates: The spatial evolution of chlorides and sulfates goes hand in hand with that of the EC by Oued Merzeg. There is an increasing gradient respectively ranging from the M1 upstream to the downstream M5 (301 to 360 mg/l and 66.53, 67.55 mg/l). While the SO site marks the lowest values (250.78 and 60.42 mg/l) (f ig Nitrates, nitrites an d ammonium: average nitrate levels evolve according to an increasing gradient (1.64 mgNO3 / l in M1 and 12.57 increase in nitrate concentrations probably result from the self- purifying to amendments of fertilizer by farmers nitrates, averages for nitrite and ammonium follow a gradient descending from upstream to downstream of the Oued Merzeg (13.85 mg NO2 / l, 26.50 mg NH4 l, 1.78 mg NH4 /l in M5) these values than those measured in the Oued Bouskoura ( _________________________ ______ ISSN 2319–1414 Int. Res. J. Environment Sci. 76 ure 2c), we note a leaching of Total phosphorus and orthophosphate : A phosphorus pollution is observed upstream of the river where the values of orthophosphate are of the order of 6.02, 3.53 mg/l in M1 and 5.46, 2.37 mg /l in M2 ( figure 2d). A decreasing gradient was observed with a reduction in downstream respectively of the order of 57.47% and 53.82%. In addition, the pollution load drained by t he SO station shows that discharges from Had Soualem has low levels of phosphorus compounds (2.65 mg /l PT and 1.38 mg /l PO ). The spatial evolution of chlorides and sulfates goes hand in hand with that of the EC by Oued There is an increasing gradient respectively ranging from the M1 upstream to the downstream M5 (301 to 360 mg/l While the SO site marks the lowest ig ure 2e). d ammonium: Along the river Merzeg, the average nitrate levels evolve according to an increasing gradient 12.57 mg NO3 / l in M4). The in the latter station would purifying effect of rivers but also by farmers in the region. Unlike the nitrates, averages for nitrite and ammonium follow a gradient descending from upstream to downstream of the Oued Merzeg / l in M1 and 1, 68mg NO2/ M5) these values are significantly higher than those measured in the Oued Bouskoura ( figure 2f) International Research Journal of Environment Sciences______________________________________________ ISSN 2319–1414 Vol. 3(6), 75-80, June (2014) Int. Res. J. Environment Sci. International Science Congress Association 77 8.148.661.953.470.691.280.002.004.006.008.0010.00M1SOM2M3M4M5 pH CE(mS/cm) Sal(g/l) Figure-2 Spatial Evolution of physicochemical parameters (a): pH, electrical conductivity (EC), salinity (Sal). (b) chemical oxygen demand (COD) and biological oxygen demand (BOD5). (c): turbidity. (d) total phosphorus (Pt), orthophosphate (PO). (e) chloride (Cl), sulfate (SO), (f): nitrate (NO), nitrite (NO) and ammonium (NH). Bacteriological characterization: Microbiological analysis indicated that the microbial load is very important and it reveals that there are signs of contamination fecal. The space variation of the load in TC, FC, FS in the various stations located on the Oued Merzeg shows important differences between the upstream and the downstream, and reveals the existence of a gradient decreasing of the upstream towards the downstream. The highest concentrations of bacterial charge (TC, FC, FS) are recorded respectively in SO (5, 62, 5,47, 4,48 Log10CFU) and are decreased in M4 (4,39, 3,95, 3,03 Log10CFU) (figure 3) as a result of the phenomenon of self-purification of streams. However, these results reveal a clear deterioration of the quality of the Oued Merzeg, while the abundance of the fecal germs values largely exceeds the standards of the water intended for consumption and irrigation. 80.7929.5750.468.2720406080100M1SOM2M3M4M5 DCO(mg/l) DBO5(mg/l) 134.1188.6920406080100120140160M1SOM2M3M4M5 Tur(NTU) 250.78390.1160.4276.55100200300400500M1SOM2M3M4M5mg/l Cl SO4 1.643.0012.5713.851.6826.5010.301015202530M1SOM2M3M4M5mg/l NO3 NO2 NH4 6.022.652.023.531.381.63M1SOM2M3M4M5mg/l Pt PO4 International Research Journal of Environment Sciences______________________________________________ ISSN 2319–1414 Vol. 3(6), 75-80, June (2014) Int. Res. J. Environment Sci. International Science Congress Association 78 Statistical Analysis: The principal component analysis (PCA) has allowed us to better understand the functioning of the Oued Merzeg from annual monitoring based on 16 variablesmeasuring, physicochemical and bacteriological9,10. The PCA results indicate that the axis F1 explains 59.78% of the total variance in the data. The F2 axis indicates 20.64% of the total variability in the data (figure 4). Thus, 80.42% of the variability of the data table is extracted by factorial F1X F2.The circle of correlation (figure 4) shows that the variables positively structuring F1 are pH, EC, Sal, Cl, SO and NO, reflecting a mineralization of waters and a significant presence of oxidized nitrogen forms (NO). While those negatively structuring F1 are PT, NH, NO, BOD, cod, PO, Turb, CF, TC ad FS. These variables describe pollution of organic type and a fecal bacterial contamination. Thus, the F1 axis can be likened to an axis translating a gradient of pollution, mineralization and fecal contamination. Whereas, the PT and PO variables contribute to the formation of the F2 axis reflecting pollution phosphoric original household.Based on factorial map F1 x F2 (figure 5), the results show that different stations are positioned (to F1) depending on the degree of pollution of their water. Thus, stations in the most polluted study (M1, M2, M3, and SO) lie on the negative side of F1, while the least polluted M4 and M5 stations lie on the positive side. Figure-3 Spatial Evolution of bacteriological parameters TC, FC, FC Projection des variables sur le plan factoriel ( 1 x 2) Active pH CE Sal Tur Pt PO4 NO3 NO2 NH4 COD BOD5 Cl SO4 LogFC LogTC LogFS -1,0-0,50,00,51,0 Fact. 1 : 59,78% -1,0-0,50,00,51,0 Fact. 2 : 20,64% Figure-4 Representation of variables on the plan factorial F1 and F2. 5.043.954.755.624.394.843.43M1SOM2M3M4M5Log10 CFU FC TC FS International Research Journal of Environment Sciences______________________________________________ ISSN 2319–1414 Vol. 3(6), 75-80, June (2014) Int. Res. J. Environment Sci. International Science Congress Association 79 Projection des ind. sur le plan factoriel ( 1 x 2)Observations avec la somme des cosinus carrés �= 0,00 Active M1 M2 M3 SO M4 M5 -5-4-3-2-1012345 Fact. 1 : 59,78% -4-3-2-1 Fact. 2 : 20,64% Figure-5 Representation of sampling stations on the factorial plan F1 x F2.Analysis of the spatial variation of these parameters allowed us to identify the following types of stations studied: In the upstream sector, M1 station draining the clean waters of the STEP Berrechid distinguished by water impacted by domestic pollution is rich in phosphorus compounds (Pt, PO) and nitrogen (NH and NO). The contribution of the latter has led to a significant increase in algae very noticed by the green colour of the water and can cause eutrophication. This pollution decreases gradually toward M2 and estimated organic loads are comparable to other water systems, like Oued Bouishak and Ouislane 11. In addition, the SO site is characterized by turbid waters with high BOD and cod levels relatively high NH4 and NO2, NO3 very low, reflecting the pollution from the industrial area of Had Soualem release. However, COD/BOD5 ratio of 1.43 agenda, which gives these releases a character of biodegradability, allows a biological purification. The pollution load of SO increases the turbidity and fecal pollution in terms of M3 located after the confluence of the waters of M2 and SO. In the downstream (M4 and M5) waters record high electrical conductivity, salinity, chlorides and sulfates, demonstrating a significant mineralization. This is consistent with the findings of other authors who mentioned that the concentration of chlorides increases continuous and proportional manner in the effect of urbanization and depending on the nature of the land crossed but still under the effect of the contributions of the tablecloth as evidenced by the work of Zerouali et al.12-16. However, high nitrogen materials (NO3) recorded at Oued Merzeg levels support the work of the ABHBC, highlighting the degradation of the quality of the coastal chaouia tablecloth by NO3, the results of this work are comparable to those reported by El ouali alami and al., higher than those reported by Abouelouafa et al. 17, 18. However, low organic pollution (COD, BOD5, Pt, PO4, NH4, NO2) and fecal (TC, FC, FS) recorded in this sector, shows an improvement of the quality of the water according to an upstream-downstream gradient, with rebates up to 83% for cod and BOD5, under the effect of the self-purifying phenomenon of the watercourse. Conclusion The present work represents a first contribution study of the quality of Oued Merzeg waters (sub-urban rivers in Casablanca) and its tributary Oued Sierni. This study allowed us to assess the degree of pollution generated by the discharge and the STEP of Berrechid and the industrial zone of Had Soualem. International Research Journal of Environment Sciences______________________________________________ ISSN 2319–1414 Vol. 3(6), 75-80, June (2014) Int. Res. J. Environment Sci. International Science Congress Association 80 The results of physico-chemical and bacteriological analyses show that qualitatively, the waters of this river are characterized by: Significant mineralization, as evidenced by the high values of electrical conductivity, chloride and sulphate at the level of all stations of the watercourse Merzeg. A high organic load and very significant fecal contamination, which persists along the waterways, resulted in the high bacterial germs concentrations of (TC, FC and FS) generated by the waters of the STEP of Berrechid and liquid effluents from the industrial area of Had Soualem. However, results obtained shows that the waters of Oued Merzeg are classified between bad and very bad quality standard of water surfaces. These results must be taken into conservation to preserve this stream, which is situated in a zone with significant tourisms, industrial and agricultural activities. References 1.Tyagi S.K., Datta P.S., Kulshreshtha S. and Sharma R.K., Isotopic and Hydrochemical Signatures in Characterizing Pollutants Movement in Overexploited Groundwater Aquifers of Delhi State (2008)2.Abu Yusof M., and Hasan N., and Pauzi Md. A., River water quality in Langat basin, Selangor, Malaysia. Malaysian Journal of Environmental Management, 3, 125-142 (2002)3.Did, Study on the River Water Quality Trends and Indexes in Peninsular Malaysia. Water Resource Publication, 21 (2009)4.Boutayeb M., Etude des performances épuratoires du traitement des eaux usées domestiques par le lagunage naturel dans la région de la Chaouia Ouardigha « Cas des STEPs de Settat, Berrechid, Ben Ahmed, El Gara et Soualem-Sahel », Thèse de Doctorat, FST Settat (2012)5.Meybeck M., Friedrich G., Thomas R., Chapman D., Rivers. Water quality assessments: a guide to the use of biota, sediments and water in environment monitoring, Chapman edition, 2nd ed. E and FN Spon, London, 59-126 (1996)6.Abhbc. , Agence du Bassin Hydraulique du Bouregreg et de la Chaouia, Etude d'évaluation des eaux de surface de la zone d'action de l'agence du bassin hydraulique du Bouregreg et de la Chaouia, mission 1, 43 (2004)7.Zerouali A., Lakfifi L., Larabi A., Ameziane A., Modélisation de la nappe de Chaouia Côtière (Maroc) First International Conference on Saltwater Intrusion and Costal Aquifers- Monitoring, Modeling, and Management. Essaouira, Morocco, April 23-25 (2001)8.Mounjid J., Cohen N., Fadlaoui S. and Oubraim S., Study of physicochemical and Microbiological quality of Oued Bouskoura: Peri-Urbain of Casablanca, Morocco. Int. Res. J. Environment Sci., 3(5), 60-66 (2014) 9.Thioulouse J., Simer M., and Chessel D. Simultaneous analisis of a sequence of paired ecological tables. Ecology, 85, 272-283 (2004)10.Eriksson E., Hydrochemistry, Chemical processes in the water cycle. Paris: Unesco (1981)11.El addouli J., Chahlaoui A., Berrahou A., Chafi A., Ennabili A. et Karrouch L., Influence des eaux usées, utilisées en irrigation, sur la qualité des eaux de l’Oued Bouishak – région de Meknes (centre-sud du Maroc), Rev. Microbiol. Ind. San et Environn. 3(1), 56-75 (2009)12.Cun C. et Vilagines R., Time series analysis on chlorides, nitrates, ammonium and dissolved oxygen concentrations in the Seine river near Paris. Sci. Total. Environ., 208, 59-69 (1997)13.Lauder G.V., Lim J., Shelton R., Witt C., Anderson E.J. and Tangorra J.L. Robotic models for studying undulatory locomotion in fishes. Mar. Technol. Soc. J., 45, 41-55 (2011)14.Bermond R., Vuichaard R., Les paramètres de la qualité des eaux. Documentation Française, Paris, 179 (1973)15.Fawzi B., Peuplement diatomique du réseau hydrographique de l’Oued Mellah : Composition, structure, autoécologie et indices de qualité. Thèse de doctorat. Faculté des Sciences Ben M’Sik (2002)16.Oubraim S., Qualité physico-chimique et biologique des cours d’eau du réseau hydrographique de la meseta occidentale Marocaine, cas de L’oued Mellah. Thèse d’état. Fac. Sci. Ben M’sik, Univ. Hassan II- Mohammedia, Casa, 208 (2002) 17.El ouali lalami A., Merzouki M., El hillali O., Maniar S. and Ibnsouda Koraichi S., Pollution des eaux de surface de la ville de Fès au Maroc : typologie, origine et conséquences, Larhyss Journal, ISSN 1112-3680, 09, 55-72 (2011)18.Abouelouafa M., El halouani H., Kharboua M. et Berrichi A., Caractérisation physico-chimique et bactériologique des eaux usées brutes de la ville d’Oujda: canal principal et Oued Bounaïm, Actes Inst. Agron. Vet. (Maroc), 22(3),143-150 (2002)